hey guys, im struggling with these 2 questions, think im getting brain freeze, must be missing something obvious. can any one help?

1.the charge Q COloumbs on a capacitor varies with time according to the formula

dQ/dt = -250sin100t

find the charge after 0.0005 seconds if Q=0.015 coloumbs at time t=0 seconds?

2. dQ/dt = 100cos200t

find the charge after 0.0005 seconds if Q=1 coloumbs at time t=pie/400 seconds?

and also, i know this is prob a stupid question but can someone tell me what

exp 1 =?

exp 0 =?

exp -1=?

thanks!!!